Method of carton erection



Feb. 8, 1966 F. c. GROSS METHOD OF CARTON ERECTION 8 Sheets-Sheet 1Filed May 4, 1964 INVENTOR.

FRANK C. GROSS ATTORNEY.

Feb. 8, 1966 F. c. GROSS METHOD OF CARTON ERECTION 8 Sheets-Sheet 2Filed May 4. 1964 INVENTOR.

FRANK C. GROSS ATTORNEY.

Feb. 8, 1966 F. c. GROSS METHOD OF CARTON ERECTION 8 Sheets-Sheet 5Filed May 4. 1964 ATTORNEY.

Feb. 8, 1966 F. c. GROSS METHOD OF CARTON ERECTION 8 Sheets-Sheet 4Filed May 4, 1964 INVENTOR FRANK C. GROSS ATTORNEY Feb. 8, 1966 F. c.GROSS 3,233,528

METHOD OF CARTON ERECTION Filed May 4. 1964 8 Sheets-Sheet 5 FRANK C.GROSS ATTORNEY.

Feb. 8, 1966 F. c. GROSS 3,233,528

METHOD OF CARTON ERECTION Filed May 4. 1964 8 Sheets-Sheet e INVENTOR.

FRANK C. GROSS ATTORN E Y.

Feb. 8, 1966 F. c. GROSS METHOD OF CARTON ERECTION 8 Sheets-Sheet '7Filed May 4. 1964 MNN ONN INVENTOR.

FRANK C. GROSS ATTORNEY.

Feb. 8, 1966 F. c. GROSS 3,233,528

METHOD OF CARTON ERECTION Filed May 4. 1964 8 Sheets-Sheet 8 INVENTOR.

FRAN K C. GROSS ATTORNEY.

United States Patent Ofi ice 3,233,523 Patented Feb. 8, 1966 3,233,528METHOD OF CARTON ERECTION Frank C. Gross, 863 Ridge Road, Wilbraham,Mass. Filed May 4, 1964, Ser. No. 364,390 1 Claim. (CI. 93-36) Thisapplication is a continuation-in-part of my copending application, Ser.No. 245,948 filed December 17, 1962.

The present invention relates to new and useful improvements andstructural refinements in methods for heat sealing together pieces orsections of paperboard, as in car-ton erecting procedures, by a systemwhich comprehends the prevention of the formation of blisters during theheat sealing and pressurizing operation and the improvement of the heatconductivity and heat sealability of the paperboard, as in the case ofcarton blanks provided with overall or spot coatings of heat scalablematerials.

Historically, in the development work preceding and leading to thepresent invention, I have been aware of the existence of the problem ofblistering, induced by the presence of the heat employed in the heatsealing function, particularly in areas of single plies or thicknessesof paperboard which are clamped between :a pair of metallic members,such as a forming mandrel and a coacting sealing plate, in manner suchas to allow the eutrapment of moisture thereat and accordingly to resultin the generation of steam from the so-trapped water vapor, all leadingto objectionable delamination of the paper board in said areas.Interestingly enough, such condition appears not to exist in areas ofdouble plies or thicknesses of paperboard so clamped between a pair ofmetallic members.

Incident to this condition and in my solution for its correction, I havediscovered that the fluting of the face of one of the metallic members,adjacent the paper board being so sealed and pressured, allows theventing of the so-generated steam sufiiciently so as to preclude theproblem ab initio.

Additionally in my developmental work, I have determined that thedeliberate and intentioned moisturizing of the paperboard, or ofportions thereof, preliminary to the heat sealing and pressurizing phaseof the working thereof, leads to improved results in the heating andsealing procedures by way of improving the heat conductivity and heatscalability characteristics, contributing to accelerated workingperiods, such as carton-erecting cycles, with obvious advantages andeconomies in time or speed thereby permitted.

Further historically, the developed moisturizing technique was resultantfrom the research and development work attendant upon the intentionaladdition of moisture to the paperboard in my effort to aggravate theblistering condition in order better to evaluate and assess the factorsinherent therein and to prove the effectiveness of the solution thereofvia the avenue of the fluting or grooving above referred to.

The embodiment of the present invention may be briefly described asembracing broadly the concept of a method of securing pieces ofpaperboard to each other as in the erection of a container blankconsisting of the sequential erecting steps comprehending: increasingthe moisture content of the pieces of paperboard or certain portionsthereof for improving the heat conductivity and heat scalabilitythereof, moving the pieces or portions thereof to be sealed togetherinto overlapping position as to each other and in clamped relationshipbetween a pair of heated metallic members, and heat pressure sealing theso clamped pieces or portions thereof with one of the heated metallicmembers being provided with fluted means for allowing the escapement ofany generated steam and precluding the blistering of the paperboard.

It also embraces the means answerable to that method which envisionscooperating instrumentalities shown in the form of a carton erectingassemblage for forming a container from a scored carton blank beingmoisturized or having certain moisturized panels by a means for foldingthe blank along certain of its score lines and heat sealing togethervarious of the moisturized panels and/ or glue tabs thereof by applyingheat and pressure thereto with one of the forming members being providedwith fluting for allowing the venting of generated steam sufficiently topreclude any blistering of the paperboard.

In accordance with the teachings hereof, the blank may first bemoisturized and the conditioned-by-moisturizing blank, and a linertherefor if one be used, may then be delivered to cooperantinstrumentation by means of which sections of paperboard are broughtinto overlapping relationship as to each other for the heat sealing andpres-surizing function between forming and pressure and sealing members,which forming member is inclusive of means allowing the escape of steamgenerated from the moisture within the paperboard for the preclusion ofthe blistering of the paperboard thereat.

While the present invention is envisioned as generally employing theprinciples, or certain thereof, of the present application, it is to benote dthat the principles of this invention may be embodied in anyapplication where pieces of paperboard are heat sealed together or inany cartonforming apparatus and/ or may be incorporated at a cartonforming station in any carton filling or packaging machine.

One primary object hereof is to teach a method aspect of heat sealingpaperboard wherewith the sequential steps of the technique may besuccessfully performed and an apparatus aspect which comprehends aconditioning and erecting and sealing assemblage associated with anapparatus which supports, and supplies movement to, a prime mover, andadditionally supports feed mechanisms for delivering a carton blank to aregistering station in adjacency to the erecting assemblage, whichassemblage is characterized by coacting stationary components fixedlysecured relative to the apparatus and movable components reciprocablerelative to the apparatus and to the stationary components of theassemblage during operational use.

With a conditioned blank, or conditioned blank and liner positionedrelative to the erecting assemblage, and with the prime mover or formingmandrel actuated theretoward, the mandrel clamps the bottom panel of theblank to a blank retainer plate of a bottom panel plate subassemblywhile the mandrel moves linearly in a cartonerecting direction toeffectuate timed articulating movements of end panel folding plates andfront and rear panel folding plates of the assemblage and consequentfolding of the end and front and rear panels of the carton tocartonerected position. Simultaneously, under conditions of heat andpressure, the overlapping moistened panels are sealed intocarton-erected position with the sealing continuing during a retrogradelinear movement of the mandrel as the plates of said assemblage traveltherewith, carrying the erected carton therewith, under actuation of areturn mechanism to return to a normal non-operative position followingcompletion of the carton-erecting cycle. Upon such return of thearticulated components of the erecting assemblage, the mandrel continuesits retrograde movement whereby to allow the freeing of the erectedcarton, or carton and liner, from the mandrel by a suitable strippingmechanism.

The invention teaches the moistening and preheating of certain of thecarton panels for attaining a conditioning of certain panels or portionsthereof which will have been pretreated with a heat sealing medium, thein seriatim folding of certain of the panels and glue tabs thereof, andthe deflecting of certain of the panels so as properly to positionthemprior to a heat and pressure sealing program, all as sequentialerecting steps, it being understood that the blank envisioned for use inconnection herewith preferentially carries overall or spot coatings of aheat-sealable medium on certain surfaces or portions of the certainsurfaces of certain of its panels tobe subjected to the said heating andpressure sealing program during the cartonerecting cycle whereby theerected end product is fully sealed in certain contacting andpermanently-bonded areas.

Heating elements for the accomplishment of the heating function aresuitably positioned on the end panel folding plates to facilitate theapplication of heat from the outside of the carton being erected and mayalso be suitably positioned on the mandrel to facilitate the applicationof additional heat from the inside of the carton. That is, it is onepurpose hereof to provide, in the case of spot coated blanks, asdifferentiated from overall coated blanks, heat and pressure sealingelements which will be disposed not only adjacent certain of the outsidesurfaces of the blank but also adjacent certain of the inside surfacesthereof, all so as to accelerate the heat sealing action and tocontribute to high erection speeds.

As one salient refinement of the invention, opposite end faces of themandrel are relieved, each to define a compensating area adjacent arespective carton-sealing area for accommodating the double thickness ofthe paperboard of a blank resulting from the overlapping of an end paneland glue tabs thereof and allowing a uniform over all contact of therespective folding and sealing plate of the assemblage with the outersurface of the respective end panels of the blank.

Additionally, and because of the fact that under certain conditions ofmachine speed, temperature, pressure, and moisture content, steam fromentrapped moisture is observed to form internally in this defined areaso as to cause the paperboard to blister and delaminate, steam ventflutes or grooves are machined into each mandrel end face thereby toobviate the condition by the provision of steam escape means. The flutesor grooves will vary as to number and as to their width and depthaccording to the thickness of the paperboard of the blank being employedand the size of the carton resulting therefrom.

Another significant object hereof is to provide a cartonerectingapparatus wherein the required heat sealing time is shortened due to apreheating feature wherewith the blank or portions thereof may be heatedprior to and during the folding phase of the erecting cycle.

Still anoth r purpose hereof is to teach methods for increasing amachine speed by augmenting the moisture content in the paperboard ofthe employed carton blanks, the effect being to reduce heat sealing timeso as thereby to allow a higher speed of machine operation.

I have determined that the moisture content of the blank is an importantfactor in the respect that, by increasing moisture content above thenormal standard, significant conditions are realized; the so-addedmoisture assists measurably in the reactivating of the heat-sealablemedium on the blank, allows the attainment of a greater bond of itsunitable parts, and increases the heat conductivity of the paper boardby reducing its insulating properties.

Different methods are envisioned for so increasing the blank moisturecontent. For instance, the blanks may be sufficiently conditioned merelyby the storage of same within a controlled atmosphere of approximately68% relative humidity for approximately 2 to 3 days preliminary tocarton-forming. Failing this, other moistureapplying methods arecomprehended and are herein taught whereby to effectuate a directapplication of the moisture to certain areas of the blank before it isdelivered or While it is being delivered to the registering stationadjacent the erecting assemblage. The moisture may be applied throughspray nozzles although the employment of roller applicators, wick typeapplicators, or like types of moisture applicators is comprehended, allin response to the desideratum of dispersing a uniform water film overthe surface or surfaces of each of the certain areas of the blank beingconditioned.

By such methods, the moisture is applied to one or the other or both ofthe surfaces of the said certain areas of the blank.

Additionally comprehended isthe use of a suitable wetting agent, incombination with the employed moisturizing medium, for facilitating anaccelerated and more effective moisture penetration.

As previously mentioned, the preheating of certain areas of the lank maybe accomplished by the use of a heated mandrel within thecaiton-being-erected and by the use of heated sealing plates without thecarton-beingerected, all for effecting a transferral of heat through thepaperboard of the blank by means of conduction to the surfaces to bebonded. By increasing the moisture content, I am able to reduce theinherent insulating properties of the paperboard, thereby to permit thehigher machine speeds at lower heat sealing temperatures.

The movable components of the erecting assemblage include a bottom panelplate subassembly which reciprocates linearly and coaxially with thereciprocating prime mover or forming mandrel and has self-aligning orfloating characteristics as respects the mandrel. Constituting saidsubassembly are a bottom plate and a blank retainer plate extendableforwardly thereof, and a pair of end panel and glue tab folding andsealing plates, each disposed at one end of the bottom plate andhingedly secured thereto so as to be movable therewith, and front paneland rear panel folding plates at opposite sides of the bottom plate andhingedly secured thereto so as to be movable therewith.

The suba-ssembly is movable in one direction in response to thecarton-erecting movement of the mandrel and in a return direction totheir normal rest positions responsive to a return mechanismconcomitantly with the retrograde mandrel movement.

The self-aligning or floating capability of the subassembly allowsheat-sealing pressure equalization on both ends of the blank during thecarton-erection cycle, the subassembly being free to adjust transverselyrelative to the main axis of movement of the mandrel.

Another chief feature hereof resides in the capacity for discharging anerected-carton from substantially the situs of the blank immediatelyprior to the initiation of the erecting process. That is to say, thearrangement hereof is not characterized by operation on the knownprinciple of thrusting or pushing an erected carton through a formingsection from one side to the opposite side thereof, but rather ischaracterized by operation on the principle of returning an erectedcarton to a point adjacent that where the blank is initially disposedpreliminary to erection.

The physical embodiments and structural details thereof as hereindescribed and illustrated are indicative of but several of the various,albeit preferred, ways in which the principles of the invention may beemployed and in which the component parts may be combined and arranged.However, said embodiments are not'intended to be exhaustive of, orlimiting of, the spirit hereof.

The precise constructions of the figures of the drawings need not beslavishly followed as, of course, various components may have to bemodified in accordance with any specific adaptation to which it is to beput. Stated otherwise, the objects are susceptible of attainment by useof constructions differing in certain respects from those dis-closed,all without departing from the underlying principles hereof.

The advantages hereof are best realized when all of its features andinstrumentalities are combined unitarily,

but useful embodiments may be produced involving less than the whole andit will be borne in mind, in the reading hereof, that all of the recitedcomponents need not necessarily be present in a single construction inorder to satisfy the spirit and scope hereof.

The novel features characteristic of my invention, as to its principlesof design and operation, and as to its construction and organization,will be best understood from a consideration of the following detaileddescription when read in conjunction with the drawings in which:

FIG. 1 is a view in top plan of an economy style of tray or carton typeblank whereon are delineated the areas or portions thereof where themoisture content is purposely augmented preliminary to thecarton-erecting program;

FIG. 2 is a view in top plan of a conventional style of tray or cartontype blank Whereon are delineated the areas or portions thereof wherethe moisture content is purposely augmented preliminary to thecarton-erecting program;

FIG. 3 is a view in top plan showing the economy style blank of FIG. 1in solid lines superimposed upon the conventional style blank of FIG. 2in phantom lines;

FIGS. 4-8 are views in end elevation, illustrating somewhatdiagrammatically and in a progressive series, the sequential steps inthe moisturizing and the folding of the bottom panel glue tabs, frontand rear and end panels, and rear panel glue tabs of an economy styleblank in the program of carton erection;

FIG. 9 is a fragmentary view in rear elevation of the partially-erectedcarton of FIG. 7;

FIG. 10 is a fragmentary view in front section of certain components ofthe prefolding mechanisms and of certain blank and liner guide andlocating member-s showing a tray blank and cooperant liner in registeredpositions before initiation of the erecting cycle and further showingthe blank moisturizing means;

FIG. 11 is a fragmentary view in side elevation of the components ofFIG. 10 with the blank and liner having been carried forwardly fromtheir station of registration by the mandrel and into their respectivepre-folded positions and further showing blank moisturizing means;

FIG. 11A is a fragmentary View in side elevation showing the steam ventgrooves in a wall of the mandrel;

FIG. 11B is a fragmentary view in end elevation showing the steam ventgrooves in the wall of the mandrel;

FIG. 12 is a View in top plan of the erecting assemblage of theinvention;

FIG. 13 is a view in side elevation showing a fully erected tray andintegrated liner, the mandrel and erecting assemblage being shown at theinward extremity of the folding and sealing cycle;

FIG. 14 is a partial view in end elevation, taken from the left of FIG.13, with portions of the mandrel and tray blank and liner guides beingbroken away for purposes of clarity;

FIG. 15 is a view in section on the line 15-15 of FIG. 13;

FIG. 16 is a fragmentary view of a tray and liner and a folding andsealing plate modified to include a spring means for pressing the linerinto heat-sealing position;

FIG. 17 illustrates, in perspective view, an economy style blankinclusive of bottom panel glue tabs, in erected position as a tray;

FIG. 18 illustrates, in perspective View, an economy style blank absentbottom panel glue tabs, in erected position as a tray;

FIG. 19 illustrates, in perspective view, an economy style blankinclusive of bottom panel glue tabs, in erected position as a cartonwith hinged cover;

FIG. 20 illustrates, in perspective view, an economy style blank withcooperant liner, in erected position as a tray;

FIG. 21 illustrates, in perspective view, an economy style blankinclusive of bottom panel glue tabs and with cooperant liner, in erectedposition as a tray, with portions of the blank being broken away forpurposes of clarity; and

FIG. 22 illustrates, in perspective view, an economy style blank absentbottom panel glue tabs but with cooperant liner, in erected position asa tray, with portions of the blank being broken away for purposes ofclarity.

In the following detailed description and appended claim, variouscomponents and details thereof are identified by specific names andterms for convenience, although such are intended to be as generic intheir application as the art will permit.

With continued reference now to the drawings, I have provided figures,in greatly simplified form and with some in semi-diagrammatic form,showing the essentials of the invention as advantageously incorporatedwithin the rudiments of a specific apparatus, all in order that thegeneral relationship and coaction of components may be betterunderstood.

It is to be understood that the apparatus may be modified to suitindividual and/or specific operating requirements. For instance, while Ihave shown a horizontallyreciprocating forming mandrel or prime mover,it will be evident that the apparatus can be suitably operated as by avertically or angularly-reciprocating prime mover, through appropriatemodification. v

I have not shown herein a means for actuating or motivating the primemover, it being comprehended that same could be caused to operate underthe influence of any suitable motivating means. Nor have I shown a meansfor feeding the blanks and/ or liners relative to the erectingassemblage, it being explained that, conceivably, feeding could beaccomplished manually or by means of feed hoppers or the equivalent forholding a supply of blanks or by means of web rolls or equivalent fromwhich sections forming liner blanks may be severed. These feedingdevices may be of any of the known styles for delivering the blanks andliners, simultaneously or in seriatim, into proper registration witheach other preliminary to erection. Nor have I shown herein a means forremoving an erected-carton from the mandrel, it being understood thatsuch discharge may be suitably accomplished by hand or mechanical means.

The economy style carton blank comprehended herein may be formed of anyfoldable material, although preferentially, it is formed of paperboard,and will carry overall or spot coatings of a heat-scalable medium oncertain surfaces or portions of surfaces of certain of its panels, whichwill be subjected to heating and pressure sealing during certain of thesequential steps in the carton-erecting operation whereby the erectedend product is fully sealed in certain contacting and permanently-bondedareas or portions thereof.

The liners comprehended for use herein may be formed of any sheeting ofa suitable film, paper or foil or laminated combinations thereof, andpreferably will have an overall heat scalable coating on one surfacethereof for sealing contact with the adjacent surfaces of the blank.

In FIG. 1, I have shown an economy style tray or carton type blank,generally indicated by numeral 10, which is die cut and prescored, itscomponent elements comprising a bottom panel 12, front and rear panels14 and 16 respectfully which are hingedly connected to the bottom panelat opposite side edges thereof along score or folding lines 18 and 20respectively, with an end panel 22 at each opposite end edge of thefront panel which is hingedly connected thereto along the respectivescore line 24, 26, with a dust flap 28 at the upper edge of each endpanel which is hingedly connected thereto along the respective scoreline 30, with a bottom panel glue tab 32 at each end edge of the bottompanel which is hingedly connected thereto along the respective scoreline 34, and with a rear panel glue tab 36 at each end edge of the rearpanel which is hingedly connected thereto along the respective scoreline 38.

Bottom panel glue tabs-32 are each provided with one end edge 40 whichis angularly-disposed relative to the longitudinal axis defined by scoreline 20, the angle being delineated by the letter A, and rear panel gluetabs 36 are each provided with one end edge 42 which isangularlydisposed relative to said longitudinal axis, the angle beingdelineated by the letter B, angle A being equal to or greater than angleB and preferentially, the sum of the angles A and B, represented by theletter C, being 90, or slightly greater than 90, for reasons to appear.

The score or folding crease lines are indicated by broken lines in flatrepresentation and in full lines in folded or partially-foldedrepresentation, except in the case of cut score 26, which is a part ofscore line 24 between front panel 14- and each end panel 22. All otherscore lines may be crease or cut scores or combinations thereof to suitthe requirements of a specific container or of a specific type ofmaterial.

In the design of a blank of such a configuration that a slit 43 isprovided so as not to require the removal of stock between end panel 22and glue tab 32, it is imperative that score 26 which is a portion ofscore line 24 constitute a cut score so as to permit the formation of asquare tray or carton. A cut score serves to eliminate the usualinterference resulting from a crease score. Such cut score 26 should beof length equal to or greater than the width of the adjacent glue tab32. Conceivably the cut score may be provided throughout the full lengthof each front panel-end panel interconnection.

Bottom panel glue tabs 32 and rear panel glue tabs 36 may be provided,on their respective outer surfaces, with a coating of a heat scalablemedium 44, according to any desired glue pattern. Reversely, suchcoating may be provided on the inner surfaces of end panels 22. It isnot necessary that both of the confrontable surfaces be so conditionedin order to effectuate successful heat sealing of one member to theother.

Such coating may be in the form of an overall coating on the selectedpanels or glue tabs or in the form of spaced, strategically-locatedspots.

If otherwise desired, in preference to preconditioning the blanks with aheat sealing medium, such medium conceivably could be applied to theappropriate surfaces of the panels and/ or glue tabs in situ at thecarton-erecting station or adjacent thereto by way of suitableinstrumentation associated with the means supporting the erectingcomponents.

Additionally, in FIG. 1, I have delineated, by means of dash lines,areas a, a at opposite ends of the blank and an area b intermediate saidareas a, a. It will be understood that the portions of the blankappearing within the bounds of each a area will be the portions of theblank, the moisture content of which will be purposely increased oraugmented by the application thereto of a film of water on one or theother or both of the sides of the blank.

I have shown, in FIG 2, a conventional style tray or carton type blank,generally indicated by numeral Stl, and comprising a bottom panel 52 andfront and rear panels 54 and 56 respectively which are hingedlyconnected to said bottom panel at opposite side edges thereof alongscore lines 58 and 60 respectively. Additionally, at each opposite endedge of said front panel, a front panel glue tab 62 is hingedlyconnected thereto along the respective score line 64, and at each endedge of said bottom panel, an end panel 66 is hingedly connected theretoalong the respective score line 68, Still further, at the opposite endedge of each said end panel, a dust flap '70 is hingedly connectedthereto along the respective score line 72;, and ateachend edge of saidrear panel, a rear panel glue tab 74- is hingedly connected theretoalong the respective score line 76.

Attention is directed to the usual removal of segments of stock betweenend panels 66 and respective adjacent glue tabs 62and 74, the necessityfor which is obviated in the case of the economy style blank carton.

Additionally, I have delineated, by means of dash lines, areas c, c atopposite ends of the blank and an area d intermediate said areas 0, c.It will be understood that the portions of the blank appearing withinthe bounds of the dash lines and Within the bounds of each c area willbe the portions of the blank, the moisture content of which will bepurposely increased or augmented by the application of a film of wateron one or the other or both of the sides of the blank.

With conjoint reference to FIGS. 1 and 2, I have shown in FIG. 3 aneconomy style tray or carton type blank 10 in superposed relation upon aconventional style tray or carton type blank 5!), to dramatize themarkedly appreciable savings of material, in the range of 15 to 25%,realizable with the economy style blank. Whereas the blanks under.comparison are shown as allowing containers of identical size, theoverall length of the economy style blank will be observed to be shorterthan the conventional style blank. It will also be apparent that aneconomy style blank may be identified as one wherein the depth, orheight, inclusive of the dust flaps, exceeds the width of theerected-carton. Such is possible when the width of the carton, whetherof tray or carton type, is less than the overall height of an end panelthereof.

In FIGS. 48, I have shown the successive or sequential stages or stepsin the erection of a die cut and prescored economy style blank into atray type carton or container according to the teaching of theinvention, in an effort first to illustrate these stages with referenceto a carton blank alone and free of instrumentation.

It will be understood that the erection of a blank of the carton or traytype incorporating an integrallyattached cover member comprisesessentially the same sequence of steps.

It will also be, understood that, while the erecting procedures areexplained hereinafter with specific reference to the economy style blank10, the procedures could apply with equal force to the blank 50 or anyother type of carton blank used in a heat sealing operation.

Further, while no cooperant liner is shown, it will also be understoodthat substantially the same sequence of steps obtains when a blank andliner are erected.

As illustrated, blank 1% will be considered to be fed verticallydownwardly into registering position'from above in the direction ofarrow D.

Preliminary to delivery to the registering position and at some selectedposition, blank 10 will be subjected to a moisturizing treatment sothatareas a, a of the blank will become wetted as by a spray of water,with or without a wetting agent additive. Such application may beaccomplished by means of a pair of applicators 131 in the form of spraynozzles, roller applicators, wick type applicators or other suitablemoisture applying means. strategically positioned relative to the pathof travel of the blank so that one or both of the sides of all surfaceswithin the areas a, a will be so treated as it moves therepast on itsway to registry position. 'Moisturizing will take place in the timedrelation to the movement of the areas a, a past the applicators 131.

Alternately, and as above alluded to, the blanks may be properlyconditioned by the storage of same within a controlled atmosphere ofapproximately 68% relative humidity for approximately 48-72 hourspreliminary to use, wherefor the moisture applying means may bedispensed with.

With further reference to FIG. 4, the blank is observed to bemoisturized by the applicators 131 on either or both sides thereofpreliminary to being positioned into a predetermined location Where itwill be in register with a mandrel which, in operation, will reciprocatealong a horizontal axis denoted by the phantom line E, firstly, in aleft-to-right direction as denoted by arrow G, and secondly, reverselyin a right-to-left direction as denoted by arrow F. Alternately, theblank could be initially fed horizontally sidewise to a position ofproper registration with a vertically-reciprocating mandrel.

In the first stage of the progression of sequential steps, representedby the showing of FIG. 4, blank 10 will be understood to be in properregister with the cooperant instrumentalities.

In the second stage of the progression, represented by the showing ofFIG. 5, bottom panel glue tabs 32 are preliminarily folded to assumeplanes approximately at 90 angles relative to the plane of bottom panel12 along respective score lines 34.

In cases where a blank and liner are erected conjointly, it is necessaryto prefold the front and rear panels 14 and 16 respectively, as shown inphantom in FIG. 5, for efiecting a control of the liner end folds andthis is so whether or not the blank is of normal type incorporatingbottom panel glue tabs or is of the type which may not necessitate same.

In the third stage of the progression, represented by the showing ofFIG. 6, the aforedescribed initial folding is followed by the allowanceof bottom panel glue tabs 32to spring back so as to assume the somewhatangular positions shown. With bottom panel glue tabs 32 hav ing sosprung backwardly, front and rear panels 14 and 16 respectively and endpanels 22 and rear panel glue tabs 36 and bottom panel glue tabs 32 arepartially fold-ed, with the folding of front panel 14 preceding thefolding of rear panel 16 in point of time.

In the fourth stage of the progression, represented by the showing ofFIG. 7, front panel 14 is observed to have been fully folded or erectedto a position where it is disposed in a plane at substantially 90relative to the plane of bottom panel 12 and end panels 22 and bottompanel glue tabs 32 are observed to have been almost completely folded,and rear panel 16 and rear panel glue tabs 36 are observed to have beenpartially folded.

conceivably, front panel 14 could be disposed in a plane greater than 90to the plane of bottom panel 12 to suit certain conditions as may berequired for a container with tapered sides.

In the sequence of steps, rear panel 16 and rear panel glue tabs 36 aredesirably not folded beyond the position illustrated in FIG. 7 until theother panels are in their illustrated positions, all to insure a properdeflection of rear panel glue tabs 36 inwardly of their respective endpanels 22. The confronting relationship of panels and glue tabs is bestillustrated in the supplemental showing of FIG. 9 wherein rear panelglue tabs 36 and bottom panel glue tabs 32 are shown to be folded androtated into their finally-erected positions before the respective endpanels 22 assume their final positions relative thereto.

In the fifth and final stage of the progression, represented by theshowing of FIG. 8, the fully-erected carton condition is illustrated.

The sequential steps of folding the blank may be summarized as: first,moisturizing the blank; second, prefolding the bottom panel glue tabs;third, deflecting the front panel; fourth, allowing the bottom panelglue tabs to spring backwardly during front panel deflection for theretaining engagement of each bottom panel glue tab behind its respectiveend panel; fifth, folding the end panels and bottom panel glue tabs andrear panel glue tabs simultaneously while the front panel is rotatedinto completely formed position and while the rear panel and associatedrear panel glue tabs are partially rotated with the rear panel glue tabsbeing deflected inwardly of the adjacent end panels; sixth, completingthe rotation of the rear panel and its associated glue tabs; seventh,bringing the end panels and associated bottom and rear panel glue istabs into sealing engagement; and eighth, venting the accumulated steamfrom areas of the end panels.

Where a blank and liner are formed simultaneously, the sequential stepsmay be summarized as: first, moisturizing the blank; second, prefoldingthe bottom panel glue tabs and the cooperant portions of the liner andsimultaneously deflecting the front and rear panels and the cooperantportions of the liner; third, allowing the bottom panel glue tabs tospring backwardly for the retaining engagement of each bottom panel gluetab behind its respective end panel; fourth, simultaneously folding theend panels and bottom panel glue tabs and the rear panel glue tabs andthe cooperant portions of the liner while the front panel and cooperantportions of the liner are rotated into completely formed position andwhile the rear panel and the associated rear panel glue tabs and thecooperant portion of the liner are partially rotated with the rear panelg-lue tabs being deflected inwardly of the adjacent end panels; fifth,completing the rotation of the rear panel and its associated glue tabsand the cooperant portions of the liner; sixth, bringing the end panelsand associated bottom and rear panel glue tabs and cooperant liner intooverlapping and sealing engagement; and seventh, venting the accumulatedsteam from areas of the end panels.

Conceivably a blankcould be employed which did not employ bottom panelglue tabs. In such instance, the sequential steps would comprise; first,moisturizing the blank; second, folding the end panels and rear panelglue tabs simultaneously while the front panel is rotated intocompletely formed position and while the rear panel and associated rearpanel glue tabs are partially rotated, with the rear panel glue tabsbeing deflected inwardly of the adjacent end panels; third, completingthe rotation of the rear panel and its associated glue tabs; fourth,bringing the end panels and the rear panel glue tabs into sealingengagement; and fifth, venting the accumulated steam from areas of theend panels.

Where such a blank, absent bottom panel glue tabs, is employed and wherea liner is simultaneously formed therewith, the sequential steps may beobserved to include: first, moisturizing the blank; second,simultaneously deflecting the front and rear panels and the cooperantportions of the liner and the prefolding of portions of the linerextending outwardly of the opposite ends of the bottom panel; third,simultaneously folding the end panels and the rear panel glue tabs andthe cooperant portions of the liner while the front panel and cooperantportions of the liner are rotated into completely formed position andwhile the rear panel and the associated rear panel glue tabs and thecooperant portion of the liner are partially rotated with the rear panelglue tabs being deflected inwardly of the adjacent end panels completingthe rotation of the rear panel and its associated glue tabs and thecooperant portions of the liner; fourth, bringing end panels and rearpanel glue tabs and cooperant liner into overlapping and sealingengagement; and fifth,

venting the accumulated steam from areas of the end panels.

Reference will now be made to the registration and prefoldingcomponents, as shown in FIGS. 10 and 11. For purposes of simplification,the framework of a supporting apparatus which aids in the positioning ofthese registration and prefolding components relatively to each other isnot shown. Any suitable conventional framework may be adapted for suchsupport function and does not constitute a part of this invention.Likevw'se, the components which support and supply reciprocatingmovement to a mandrel 10%) and the feeding mechanism which delivers theblank from a stack or magazine or equivalent supply means and acooperant liner, if one be used, from a stack or roll or equivalentsupply means, to the registration point or station are not shown, andagain for the reason that same do not constitute parts of thisinvention.

With reference to FIG. 10, a blank and liner L will be understood tohave been delivered simultaneously, or in seriatim, to their respectivepositions of registry in substantial face-to-face relationship with eachother at the socalled registration station.

ln moving to said station, the blank is caused to move past the pair ofstrategically-positioned spray nozzles 131 for purposes of moisturizingareas a, a of the blank. Such spray means may be disposed at oppositesides of the path of travel of the blank, if moisturizing of bothsurfaces of the areas a, a is desired.

The outer edge portions of end panels 22 of the blank are eachreceivable within the adjacent inwardly-facing vertically-disposedregistration slot 102 provided in a vertically-disposed blank guide 106at each side of the registration station. The blank guides are arrangedin spaced parallelism as to each other and are each provided with aninwardly-facing vertically-disposed registration slot 1&2. Being spaced,they allow sliding accommodation therebetween of a blank in mannerwhereby the outer edge portions of the blank end panels 22 are slidablyreceivable within the respective registration slot 102.

Blank guides 1&6 may be adjustably positioned relative to suitable framemembers of the support means whereby they may be variably positioned soas to serve blanks of different dimensions.

Rearwardly of each blank guide 106 and adjustably secured thereto bysuitable means, not shown, is a vertically-disposed liner guide 104 toallow a pair of such liner guides strategically located in spacedparallel relationship as to each other on opposite sides of theregistration station and in a vertical plane immediately and rearwar-dlyadjacent the vertical plane of blank guides 196. Said liner guidesproject inwardly toward the center of the registration station andextend inwardly beyond the vertical plane defined by the registrationslot 102 of their respective blank guides. Being adjustable, thepositioning of liner guides Hi4- relatively to blank guides 106 may bevaried to the accommodation of blanks and liners of varying dimensions.

With a blank being receivable within the registration slots of the blankguides, sufficient clearance is allowed for the reception therebehind ofa liner so that the opposite side edge portions of the liner will besupported by and forwardly of the respective liner guides.

Within and at the lower portion of each registration slot W2, an insert108 is removably receivable. Each insert is provided with an upperinwardly-inclined surface 110 and an inner vertically-disposed surface112, which surfaces are disposed in pairs on opposite sides of theregistration station and serve conjointly to center the lineras same ismoved vertically into registering position. Said inserts may be adjustedin their positions relative to the respective slots, or may be replacedwith inserts of other configurations but of identical purpose, so as toaccommodate blanks and liners of different dimensions.

Forwardly of and adjacent the lower extremities of liner guides 104 andvertically beneath the lower extremities of blank guides 1%, a pair ofcoaxially-disposed liner stops Eldare adjustably secured to said linerand blank guides by suitable means in manner to close the lower open endof the respective registration slot 102 and to allow aligned uppersurfaces 116 which the lowermost edge of liner L will abut, as itassumes its registering position.

Liner stops 114 may be vertically adjusted relative to liner guides N4and blank guides 106 so as to vary the positioning of the accommodatedliners L, all whereby liners of varying dimensions may be served.

Strategically located within each registration slot 162, a blank stop118 is adjustably secured by suitable means. The blank stops of the pairthereof are horizontally aligned as to each other to allow a limitshoulder at each side of the registration station against which the edgeof one of the blank end panels 2?. abuts as the blank assumesregistering position.

Adjustably secured to each liner stop 114, by suitable means in mannerto project upwardly and forwardly thereof, is an inclined rear panel andliner guide and prefolder 122 which may be adjusted relative to saidliner stops to accommodate blanks and liners of varying sizes.

Said rear panel and liner guides and prefolders function operationallyto initiate guiding and prefolding of rear panel 16 of the blank, andthe liner when and where used, delivered to the registering station andin the process of being pushed forwardly therefrom by mandrel 100.

For simultaneously erecting a blank and liner, there will beadditionally provided a pair of adjustable horizontally-spaced,parallel, fingerlike front panel and liner prefolders 126, which projectdownwardly from the frame of the apparatus in a vertical planeimmediately forwardly of the vertical plane defined by aregistered-in-position blank and liner. They function operationally toinitiate prefolding of the blank front panel 14 and the liner deliveredto the registering station, as they are pushed forwardly therefrom bymandrel flit. Said front panel and liner prefolders may be adjustablypositioned relative to the registration station to accommodate blanksand liners of varying dimensions.

On the outwardly facing side thereof of each blank guide 1% an inwardlyand forwardly inclined bottom panel glue tab folder 128 is adjustablysecured by any suitable means, they being horizontally aligned as toeach other, and extending generally inwardly toward each other inwardlyof the vertical plane defined by its respective blank guide a distancesufiicient to assure confrontation with the respective bottom panel gluetab and the deflection thereof as mandrel ltltl moves forwardly throughthe registration station to drive the blank, or the blank and liner,therewith.

The registration station is defined as being that area bounded by thepairs of liner and blank guides, the pair of liner stops and theassociated pair of rear panel and liner guides and prefolders, the pairof front panel and liner prefolders, and the pair of bottom panel gluetab folders. Through said registration station, the mandrel 109 ismovable transversely relatively thereto in a forward carton-erectingdirection from a position rearwardly of the registration station to aposition forwardly thereof and also to be movable reversely in aretrograde carton-sealing-and-pressurizing and erected-carton-ejectiondirection.

As the forward face of mandrel 106 projects through the registrationstation, bottom panel 12 of the blank, and the adjacent portion of theliner if one is used, are in registration with the bottom face of themandrel so as to be projected forwardly therewith, asshown in FIG. 11,with bottom panel glue tab folders 12% serving to deflect the respectivebottom panel glue tabs 32 and adjacent liner portions rearwardly, andwith front panel and liner prefolders 126 serving to deflect the frontpanel 14 and adjacent liner portions rearwardly, and with rear panel andliner guides and prefolders 122 serving to deflect the rear anel andadjacent liner. portion rearwardly, the simultaneous prefolding featuresthus represented being essential properly to control the initiation ofthe liner folds, particularly in the corner areas at the opposite endsof the liner.

The blank and liner will be observed, in FIG. 11, to be located not onlyat the so-called prefolding station of the carton-erection program butalso at the, station where the bottom panel of the blank is inconfiguration with a blank retainer plate 32%, subsequently to bedescribed, which blank retainer plate is projected into blank retainingposition outwardly of the plane of a bottom panel plate 310, said blankretainer plate serving to'hold the blank and liner in positions ofregister as to each other and as to the bottom face of the mandrel assaid mandrel moves the blank and liner past prefolders 12-2, 126' and128 and into engagement with the folding and sealing components.

Said blank retainer plate 320 will be spring-loaded with respect to aslide shaft 220 supporting the bottom plate 310 by a spring means 328.

The blank and liner having so been driven forwardly, bottom panel 12 ofthe blank first confronts the erecting, or forming and sealing,assemblage aligned with the mandrel and disposed forwardly thereof,which erecting, or folding and sealing, assemblage is stationarily orrigidly fixed to the same supporting construction accommodating theregistering and prefolding instrumentation and comprises a plurality ofstationary or fixed components which, during operational use, remain infixed positions relative to the assemblage and supporting structure anda plurality of movable components which, during operational use, movecooperantly according to the dictates of mandrel 199 in a forward,carton-erecting direction and of an air cylinder or equivalent springreturn means (to be described) in a rearward or retrograde movement.

The stationary or rigidly fixed components of the assemblage aredescribed as constituting a pair of spaced horizontally-extendingcross-braces 260 held in separated parallel relationship as to eachother by a suitably configured spacer 202 disposed therebetween andsecured thereto as by a bolt 204 and nut (not shown) adjacent each endsection of the interrelated cross-braces, and a pair of spacedvertically-extending posts 210 similarly held in separated parallelrelationship as to each other by other spacers (not shown) and disposedtherebetween and secured thereto. The employment of such spacers allowsthe adjustable spacing of the cross-braces as to each other and theadjustable spacing of the posts as to each other. Said cross-braces andposts are arranged in crossing right angular relationship as to eachother, with the cross-braces disposed in a vertical plane forwardly ofthe vertical plane of the posts, as viewed in FIG. 13, and the pair ofcrossbraces and the pair of posts being secured to each other as bypairs of gibs, one forward pair of suitably notched gibs 212 beingsecured to the forwardly-facing faces of the cross-braces as by bolts214 and one rearward pair of suitably-notched gibs 216 being secured tothe rearwardlyfacing faces of the posts as by bolts 218, said gibscooperating for holding in place a horizontally-arranged slide shaft 22%as adjusting or take-up shoes functioning to allow a proper sliding fittherebetween and taking-up for wear through continued service.

Slide shaft 22% is provided along its length with a square portion 221,and a relieved cylindrical portion 223. During the folding portion ofthe cycle, square portion 221 is accurately guided in the sets ofnotched gibs 212 and 216 for maintaining proper component registration.During the sealing portion of the cycle, cylindrical portion 223 entersthe first set of gibs to allow the entire assembly to float Withincertain predetermined limits, thereby to pro vide a self-aligningfeature for aiding in the equalizing of heat sealing pressure.

With references to FIG. 12, the rearmost end of slide shaft 220 issuitably threaded to receive the forwardmost end of ahorizontally-disposed coaxially-aligned piston rod 236 extendingforwardly from a rearmost-located air cylinder 232, which air cylinderis provided with suitable air connections 234 for appropriate connectionto a source of air supply (not shown) in known manner. The air cylindermay be suitably supported in a generally horizontally-disposed positionas by a vertically-disposed end plate 236 which the air cylinderembraces and through a central opening of which the piston rod andsecuring means on the end face ofthe air cylinder extends. The securingmeans is adapted to be threadedly engaged as by a nut 238 wherewith theair cylinder is clamped to the end plate. A pair of spaced air cylindersupport brackets 240 have rearmost end portions which areinterengageable with said end plate as by bolts 242 and nuts 244 andhave forwardmost end portions which are interengageable each with a sideface of one of the posts as by bolts 246, to the end that the aircylinder is supported relative to the rest of the erecting assemblage.

A front panel actuating roll arm support bracket 25%), disposed inhorizontal alignment with and vertically above slide shaft 220, isfixedly secured to posts 210 of the pair thereof as by forward andrearward bracket clamp plates 252 and 254 respectively which aredisposed against the forward and rearward faces of the postsrespectively, with bracket 25h being clamped between the forward clampplate and forward faces of the posts as by bolts 256. Similarly, a rearpanel actuating roll arm support bracket 260, disposed in horizontalalignment with and vertically below slide shaft 220, is fixedly securedto the posts of the pair thereof as by other forward and rearwardbracket clamp plates 262 and 264 respectively which are disposedadjacent the forward and rearward faces of the posts respectively, withbracket 260 being clamped between the forward clamp plate and forwardfaces of the posts as by bolts 266.

Vertical adjustment of brackets 250 and 260 relatively to the posts isallowed by a loosening of bolts 256 and 266 respectively, a manualmovement of the brackets, and a retightening of the bolts when thebrackets have assumed desired readjusted positions.

Brackets 250 and 260 are suitably slotted at 268. A front panelactuating roll arm 270 and a rear panel actuating roll arm 280 are eachslidably engaged with the respective bracket as by a bolt 272 extendablethrough the slot of the bracket and threadedly engageable in therespective actuating roll arm. The front and rear panel actuating rollarms are each forwardly and rearwardly movable relative to theirrespective brackets by a loosening of bolt-272, a desired adjustmentmovement of the actuating roll arm relative to the bracket, and aretightening of the bolt.

Transversely-arranged front panel and rear panel actuating rolls 274 and284 respectively are suitably journalled in the forward ends of frontand rear panel actuating roll arms 270 and 280 respectively.

In operation, front panel actuating roll 274 will be desirably disposedin a vertical plane forwardly of the vertical plane of rear panelactuating roll 284-.

At each side of slide shaft 220, an end panel folding and sealingbracket 290 is adjustably secured to the forward faces of the pair ofcross braces 200 as by a bolt 292 extendable through an apertured plate294 and through the space allowed between the cross braces andthreadedly engageable with a foot portion of the respective said foldingand sealing bracket.

Each said end panel folding and sealing bracket will be suitablybifurcated or otherwise configured to allow reception therethrough of anend panel folding and sealing arm 296 pivotally mounted relatively toits respective bracket as by a pin 298, said arm having atransversely-arranged end panel folding and sealing roll 300 suitablyjournalled in its forward end and having a transversely-extendingspring-loaded bolt 302 threadedly engaged therewith at its rearward endserving to urge the rearward end of the arm away from the longitudinalaxis defined by slide shaft 220 and to bear against an adjustable stopmeans 304 threadedly secured to the respective end panel folding andsealing bracket, all whereby the forward end of the arm is urged towardthe longitudinal axis of slide shaft 226.

The blank retainer plate 320 of the bottom plate subassembly isinterconnected to and guided relative to bottom plate 310 by means of ablank retainer plate support pin 322 centrally located relative to therearwardly-facing face of the blank retainer plate and having an outerend fixedly secured thereto by appropriate means. The said pin is ofsuch length as to allow its opposite end portion to be receivable withina suitable longitudinal bore extending through said slide shaft and tobe retained therewithin by means of an enlarged head 324 at the saidopposite end of said pin, which head abuts against an in- 15wardly-extending radially-arranged slide shaft limiting shoulder 326wherewith the forwardmost positioning of the blank retainer platerelative to the bottom plate is predetermined.

The spring-loading feature of said blank retainer plate is provided by aspring means 328 sleeved within the slide shaft bore and having aforwardmost end bearable against pin head 324.

A blank retainer plate guide pin 33f) transversely-spaced from pin 322is secured at the forward end to the rear face of said blank retainerplate and is of such length that its rearward end is extendable throughan opening extending through said bottom plate, whether the blankretainer plate be in its normal forwardly-extended position of restspaced from the bottom plate or in its rearwardly-extended position ofcompression for operating whereat it is flush with the face of thebottom plate, wherewith the blank retainer plate is guided and squaredrelatively to the bottom plate. Said normal or rest blank retainer plateposition, forwardly of the bottom plate by virtue of said spring loadingis shown in FIG. 11.

An end panel folding and sealing plate 346 is pivotally connected tobottom plate 310 at each end thereof as by a pivot pin 342. Means may beprovided for adjusting the positioning of said pivot pins transverselyrelative to the bottom plate for adjusting the location of the end panelfolding and sealing plates relative to the bottom plate, all wherebyblanks of different dimensions may be accommodated by the sameassemblage.

The opposed end panel folding and sealing plates 34% are interconnectedby means of a pair of springs 344 extendable therebetween astride and onopposite sides of slide shaft 220, each spring being engageable at itsopposite extremities with an adjacent spring stud 346 projectingoutwardly from its respective end panel folding and sealing plate 349,Wherewith the end panel folding and sealing plates are urged intonormally open rest position where they are disposed in planes slightlyangular relative to the plane of the face of bottom plate 310. When theend panel folding and sealing plates are actuated into operatingposition, springs 344 are loaded so as to urge the plates to return totheir normal open rest positions upon relief from their operativefunctions.

A cam member 350 is fixed to the rearward face of each end panel foldingand sealing plate as by bolts 352 and is provided with a cam face 354and a pressure dwell 356. The adjacent pressure roll 390 isoperationally adapted to be rollable along said cam face to provide therequisite dwell time during the sealing phases of the carton erectingand retrograde travel of the mandrel and the bottom plate subassemblyand the end panel folding and sealing plates travelling therewith.

Bottom panel and rear panel glue tab deflector plates 341 may be fixedto the forward faces of each of the end panel folding and sealing platesand may comprise a step or offset serving in point of time to be broughtinto confrontation with the respective said glue tabs before therespective end panels are brought into confrontation therewith.Alternatively, instead of deflector plates being stat-ionarily secured,offsets could be machined into the forward faces.

In FIG. 13, I have illustrated a rear panel glue tab 36, in phantom, outof folding sequence, merely to show same as resting against a deflectorplate 341.

Cartridge heaters 358 or electrodes for dielectric sealing or equivalentconventional heating means (not shown) are disposed in appropriatecavities or recesses within each end panel folding and sealing plate andwithin the mandrel, with appropriate energization and control meansbeing associated therewith. Here again same are not shown for purposesof simplification.

A front panel folding plate 360 is secured to the face of a rollerengaging member 364 which is pivotally engaged as by a pivot 352 tobottom plate 310. On the outer surface of the member 364, the adjacentactuating roll 274 is operationally adapted to be reliable along therearward face thereof to provide the requisite front panel foldingaction during carton-erecting travel of the bottom plate subassembly andthe' front panel folding plate travelling therewith.

A rear panel folding plate 379 is secured to the face of a rollerengaging member 3'74 which is pivotally engaged as by a pivot 372 tobottom plate 3&0. On the outer surface of member 364, the adjacentactuating roll 284- is operationally adapted to be rollable along therearward face thereof to provide the requisite rear panel folding actionduring carton-erecting travel of the bottom plate subassembly and therear panel folding plate travelling therewith.

Torsion springs 37%, provided for returning the front and rear foldingplates to normal rest positions, are sleeved upon the respective pins352 and 372 between bottom plate 31d and a suitably positioned collar379.

T he apparatus of the invention is such as to allow the performance ofall of the prefolding and folding and sealing operations in a series ofsequential steps in a single cyclic movement.

The initial stage of the operation comprehends the registering at theregistration station of the blank relative to the mandrel, or, where aliner is used therewith, the registering of the blank and liner relativeto each other and to the mandrel. So registered, the mandrel is actuatedin its carton-erecting direction so as to embrace, with its bottom face,the carton bottom panel, or the portion of the liner adjacent the cartonbottom panel where a liner is employed, and to urge the blank, or theblank and liner, toward the blank retainer plate, with the end panelglue tabs and the front and rear panels being deflected from theircoplanar relationship with the bottom panel as the bottom panel isclamped between the mandrel face and the opposed face of the blankretaining plate.

The end panel and glue tabfoldi-ng and sealing plates and the front andrear panel folding plates are strategically positioned to each other soas to allow such actuation thereof in point of time that the front panelfolding plate first achieves a full folding of front panel 14 (i.e. afold of between front panel 14 and bottom panel 12) while each end panelfolding and healing plate has achieved an almost complete folding of itsassociated end panel 2-2 and bottom panel glue tab 32 and rear panelglue tab 36, and rear panel glue tab deflector plates 341 havingdeflected their respective glue tabs forward of end panels 22, while therear panel folding plate has achieved only a partial folding of rearpanel 16.

Continued carton-erecting motion of the mandrel next assures fullfolding of the rear panel folding plate and consequent erection of therespective rear panel and rear panel glue tabs therewith, with the endpanel and glue tab folding plates continuing their respective movementsto bring the end panels and glue tabs into sealing position.

In FIG. 13, mandrel 109 and the erecting assemblage will be observed tobe positioned at the inward end of the carton-erecting direction ofmovement. Rollers 274 and 284 have urged front and rear panel foldingplates 366) and 37th into fully erected position. Simultaneously,rollers 300 have urged their associated end panel folding and sealingplates 346 into fully erected position, all to the end that an erectedtray or container is formed.

The preheating time of the end panels and glue tabs of the blank, andthe overlapping end folds of the liner, when used, is represented as thetotal time during which the end panels and glue tabs are sufficientlyclose to the end panel folding and sealing plates as to be heatedthereby. The heat seal-ing time of the end panels and glue tabs and theoverlapping folds of the liner is represented as the total time duringwhich the end panels and glue tabs and overlapping folds of the linerare subjected to the pressure of the end panel folding and sealingplates by their respective pressure rolls in carnrned relationship withthe cam mem- 17 hers thereof during the sealing portion of thecartonerecting travel of the mandrel and during the sealing portion ofthe retrograde travel thereof.

The opposite end faces of mandrel 100 are relieved as at 101 to definean area adjacent the canton sealing area for purposes of compensatingfor the double thickness of the paperboard resulting from theoverlapping of an end panel and glue tab. Such relief allows uniformoverall contact of the folding and sealing plates with the outersurfaces of the end panels. A single thickness area of each end panel issubject to heat and pressure during the heat seal-ing portion of acycle. Under certain conditions of machine speed, temperature, pressure,and moisture content, steam will form internally in this area to causethe paperboard to delaminate and form blisters. To prevent such, steamvent grooves 103 are machined into this area of both ends of themandrel. These grooves may vary in width and depth to suit the thicknessof paperboard being employed. Likewise the number of grooves requiredmay vary with respect to the size of the carton.

As an additional feature, the outermost face of blank retainer plate maybe faced by a lining 321 of soft, resilient material, such as spongerubber or the like, and the confronting bottom face of the mandrel maybe relieved for accommodating of the said face of said blank retainerplate.

By the coaction of the so-constituted blank retainer plate and bottomface of the mandrel, bottom panel 12 of the blank will be observed to bedeformed inwardly, under pressure so as to overbreak along score lines18, 20 and 34 beyond 90 wherefore a more-squarely formed carton results.

The slide shaft will be observed to be provided with a relieved portion223 for the purpose of allowing a floating feature during the sealingpart of the cycle where the relieved portion of the slide shaft entersthe first set of gibsto allow the entire movable assembly to float acontrolled amount and to be self-aligning wherewith the heat sealingpressure is equalized.

By the heat sealing means, the interengagement of the outer face of eachglue tab and a portion of the inner face of the related end panel isrealized.

When the forming mandrel is released and withdrawn outwardly, the nowerected carton travels with the mandrel until acted upon by suitablypositioned stripper fingers (not shown).

The apparatus hereof does not push the formed carton through the formingsection, in contradistinction from most prior art devices, but ratherreturns it to a point distantly of the forming section for dischargetherefrom, all to the end that the length of the stroke required for themandrel is appreciably reduced, a feature especially advantageous in thecase of formed cartons incorporating hinged covers.

The retrograde movement of the mandrel allows the concomitant movementof the slide shaft by the air cylinder so as to lead to the return, tonormal rest positions, of the bottom panel plate and of the end foldingand sealing plates, and of the front and rear folding plates coplanarwith or almost coplanar with the bottom plate.

When and as the bottom plate comes to its rest position, the continuedretrograde movement of the mandrel serves to allow the followingtherewith of the spring load ed blank retainer plate so as to assume itsrespective position of rest.

By the unique arrangement hereof, I provide for the forming of a cartonor tray from an economy style blank by themselves or simultaneously witha cooperant liner.

Such is allowed by means of a mechanism wherein the heating and pressurescaling functions are performed during a portion of both the in and ontravel of the mandrel, and wherein the end folder and sealing plates arehinged to the bottom plate and are self-alignable therewith so as totravel with the carton or tray, with or without its cooperant liner,while it is being formed and sealed and to permit the equalization ofthe heat-sealing pressure exerted upon the respective end panel of thecarton.

In FIG. 16, I have illustrated, in partial section, a formed cartonblank 10 and cooperant liner L in combination with an end panel foldingand sealing plate 340 wherein a pair of spring like members 343 and 345cooperate to exert pressure directly against the upper or outeroverlapping seam of the liner and against the dust flap adjacent theoverlapping seam of the liner so as indirectly to bear thereagainst allso as to heat seal the portions of the overlapped seam of the lineroutwardly of the respective end panel folding and sealing plate.

In FIGS. 17-22, I have illustrated formed containers or trays erectedfrom the economy style blank of the invention with and without cooperantliners.

In FIG. 17, I have shown the economy style blank 10 of FIG. 1 erected asa tray incorporating the bottom panel glue tabs 32.

In FIG. 18, I have illustrated an economy style blank erected as a traywherein the bottom panel glue tabs have been eliminated, a sometimesdesired arrangement.

In FIG. 19, the economy style blank erected as a carton and modified toinclude a cover 17 and cover flap 19 has been illustrated.

In FIG. 20, I have shown the economy style blank with liner L cooperanttherewith, same being in erected position as a lined tray.

In FIG. 21, I have shown a lined tray with certain panels of the traybeing broken away for the sake of clarity wherein the rear panel gluetab 36 and the bottom panel glue tab 32 at the exposed end are clearlyshown.

The lined tray of FIG. 22 is similar to the lined tray of FIG. 21 exceptthat the bottom panel glue tab 32 has been omitted, as is sometimesdesired.

By the method and apparatus hereof, I attain the simultaneous foldingand sealing of a liner with a tray or carton wherein the liner iscompletely sealed so as to allow a moisture-proof dust-proof arrangementaccording to the specific types of liner materials being employed, andfurther wherein the folds of the liner are interlocked with each otherand the liner is adhered to the inside of the tray or carton in certainareas so as virtually to olfer a one piece construction.

Although my invention has been described and illustrated herein withparticular reference to specific carton forming structures, it should beappreciated that its utility and application extend beyond theparticular types illustrated and its broad scope and concept comprehendthe useful and novel features set forth when combined with any type ofcarton forming mechanism and thus, with respect to the scope of theinvention, the foregoing material is to be considered as illustrativerather than limiting.

The invention is susceptible of various modifications and alternativeconstructions, and it is to be understood that I do not thereby intendto limit the invention to the specific forms above disclosed, but intendto cover all modifications, variations, alternative constructions andequivalents reasonably falling within the spirit and scope of theinvention as expressed in the appended claim and within the meaning andpurview and range of equivalents of this disclosure.

I claim:

In the method of erecting a paperboard carton blank into a formedcontainer by heat sealing together portions of the paperboard cartonblank, the sequential steps of, increasing the moisture content of thepaperboard carton blank preliminary to erection for improving the heatconductivity and heat scalability of the paperboard carton blank,folding and rotating the panels and glue tabs into completely-formedposition with the glue tabs deflected inwardly of their respectivesealing panels for bringing the respective scalable components into heatsealing engage- References Cited by theExaminerment between a formingand sealing member interiorly of the erected carton and folding andsealing members eX- UNITED STATES PATENTS teriorly of the erected cartonwhile allowing the escape 2,268,477 12/1941- Elmelfldorf of expandedtrapped moisture in the paperboard blank 5-. 2,987,105 6/1961 Gebblethrough venting grooves in the adjacent faces of the form- 3,085,4794/1963 Hoyrup et 93 51 ing member to prevent the formation of blistersdue to paperboard delamination caused by the expansion of the FRANKBAILEY Prlmary Exammer' trapped moisture. BERNARD STICKNEY, Examiner.

